Black ash firewood: BTU, weight and seasoning

Heat per cord

Black ash is a hardwood. At 20% moisture, a full cord holds about 19.9 million BTU of heat (21.0 gigajoules). Wetter wood gives less, because part of the heat goes into boiling off the water.

That ranks black ash 433rd of the 558 species in our tables, from the hottest down.

Weight and density

A full cord of seasoned black ash (20% moisture) weighs about 3,230 lb (1,470 kg). Freshly cut, the same cord weighs about 3,880 lb (1,760 kg): the difference is water you don't want to burn.

Its specific gravity, a measure of density, is 0.55. Denser wood packs more heat into each cord.

Seasoning time

Split and stacked off the ground, black ash needs at least 8 months to dry to about 20% moisture.

Wood dries faster once it is split and stacked with air around it. A moisture meter on a fresh split face tells you when it is ready.

How it burns

• Ash: moderate
• Coals: high
• Burn time: long

We rate black ash 3 out of 10 as firewood: it burns, but denser species give more heat for the same work.

Similar firewood

Other species to compare with black ash:

• Green ash: 23.4 million BTU per cord
• Tamo ash: 20.4 million BTU per cord
• White ash: 24.6 million BTU per cord
• Silver maple: 19.3 million BTU per cord

Where these numbers come from

The heat and weight figures come from our firewood tables, worked out the same way for every species at 20% moisture. See how we calculate them.

Questions